do AAVs expel sewer gases?

Users who are viewing this thread

Messages
58
Reaction score
0
Points
6
Location
Baltimore, MD
This may be a stupid question but if an AAV remains closed until it receives negative pressure from water going down the drain then how does it expel sewer gases? What happens to them if you use an AAV?
 

Reach4

Well-Known Member
Messages
38,796
Reaction score
4,412
Points
113
Location
IL
A properly-operating AAV only admits air. Sewer gases will make it out of the sewer after or during the sewage passage. Eventually it will go by a vent.
 

Terry

The Plumbing Wizard
Staff member
Messages
29,942
Reaction score
3,458
Points
113
Location
Bothell, Washington
Website
terrylove.com
An AAV needs a proper vent somewhere in system for postive pressure. There should be at least one vent through the roof for that.


studor_specs.jpg
 
Last edited:

hj

Master Plumber
Messages
33,602
Reaction score
1,038
Points
113
Location
Cave Creek, Arizona
Website
www.terrylove.com
I question item E, because there is no way to "engineer design" the installation to vent trapped air in an ejector pit if there is no "atmospheric vent" and/or the water in the pit rises above the inlet piping.
 

Tom Sawyer

In the Trades
Messages
3,625
Reaction score
34
Points
48
Location
Maine
Well now HJ, if you log on to the Studor web site you can find an engineered drawing for just such a thing. Of course, as you look at it you will note that the way they have the AAV installed it pretty much does nothing. LOL
 

Terry

The Plumbing Wizard
Staff member
Messages
29,942
Reaction score
3,458
Points
113
Location
Bothell, Washington
Website
terrylove.com
I think most of the plumbers would refuse to use them on a pumped system.
I remember on one basement installation where I went to the next floor and used the 2" toilet vent.
 

Asktom

Member
Messages
745
Reaction score
32
Points
18
Location
Victor, MT
AAVs are lazy plumbing. They will eventually fail, no matter how the Studor folks frame it. AAVs are from the "wham bam thank you mam" school. Gravity, which includes atmospheric pressure, will continue to work indefinitly. Vent it right and it is a done deal.
 

Tom Sawyer

In the Trades
Messages
3,625
Reaction score
34
Points
48
Location
Maine
Honestly, other than an island sink and even there I'd rather waste stack vent, I have never in near 40 years of plumbing installed one and never will. I have always been able to find a way to properly vent the fixture and if the homeowner doesn't want the expense or possibility of having to do sheet rock repairs, I walk away from the job. Not interested in hack work and better than that, I don't need it either. Then again I feel the same way about PEX, flexible supply tubes and plastic J hook hangers. We don't stock any of the above, don't use any of the above and I would probably fire any plumber working for me that did. Add CSST for gas piping to the list LOL
 
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks